Electric-alarm operating mechanism



(No Model.) I

P. O. THOMPSON. ELECTRIC ALARM OPERATING MECHANISM.

No. 526.760. Patented Oct. 2,1894.

I qw Hmwma I UNITED STATES PATENT OFFICE.

PARKER o. THOMPSON, or ELMIRA, New YORK.

ELECTRIC-ALARM OPERATING MECHANISM.

SLECIFICATION forming part of Letters Patent No. 526,760, dated October 2, 1894.

Application filed December 19, 1893. Serial No. 494,019. (No model.)

To atZZ whom it may concern.-

Be it known that I, PARKER (J. THOMPSON, of Elmira, county of ()hemung, State of New York, have invented certain'new and useful Improvements in Electric-Alarm Actuating Mechanism, of which the following is a specification, reference being had to the accompanying drawings. I

The object of my invention is to produce a [0 simple, convenient and effective device for sounding an alarm for a short interval of time, and is adapted to be used upon store doors, or the like, where it is desirable to have an alarm sounded upon the entrance of a customer and Where a continuously sounding alarm is objectionable.

Generally speaking, my invention, there fore, consists in a device for sounding an electric alarm and automatically interrupting the same after the lapse of a suitable length of time.

In the accompanying drawings: Figure 1 is a side elevation of my device complete. Fig. 2 is a top plan view thereof; and Fig. 3

is an enlarged section on the line a;0c of Fig. 1.

Referring to the figures on the drawings: 1 indicates a frame plate which may be made of any suitable conductive material, as for example, iron.

2 indicatesa metallic longitudinallygrooved track pivotally carried upon the frame upon a fulcrum piece 3 secured thereto nearer one end than the other.

4 indicates a ball moving in the groove of the track and of a weight sufficient, when on the shorter end, to counterbalance the longer end of the track. A guard piece 5 is secured to the long end of the track to prevent the dislodgement of the ball at that end.

6 indicates abinding post in electrical communication with the frame and with the live wire.

7 indicates a binding post preferably insulated from the frame, but in electrical communication with the post 6.

The wires 8, shown in the drawings, communicate with a suitable electric bell, not illustrated, and with a source of electrical 5o supply, also not illustrated.

carried upon the track 2. When the ball is at the short end of the track the contact between the points 9 and 10 is broken and no current passes. If, however, the weight of the ball is transferred, so as to allow the depression of the bridge, the contact will be made through the points 9 and 10 and a circuit be established through the track and the frame between the two binding posts. The electric bell will become active so long as this contact continues, but will be immediately silenced when the contact is broken. For effecting the automatic operation of the ball, the track is, when the plate is fixed, as for example to the frame of a door, slightly inclined toward its short end so that the ball normally seeks that point. A spring-actuated arm 11 carried on a stud pin 12 projects in the path of the ball. A trip latch 13 adapted to be carried on a door moves in the path of the latch 14 that is yieldingly secured to the arm so that when the latch moves in one direction it is allowed to pass freely, as in shutting the door, but when it moves in the other direction it draws back the arm in opposition to the force of its spring and when it is re-' leased, the arm strikes a blow against the ball and drives it toward the guard plate 5. In this manner the contact between the points 9 and 10 is effectedin a short space of time, the incline of the track carrying the ball back to its initial position, after a predetermined period, depending upon the inclination and length of the track, has been accomplished.

I do not confine myself to the exact details of construction herein shown and described but reserve to myself the right to modify and vary them at will within the scope of my in- Vention.

What I claim is- 1. The combination with a frame adapted to be placed in communication with an electric bell, of a track pivoted thereto, contact pieces on the frame and track, a ball weight movable on the track, mechanism independent of the track for driving a ball, and means for actuating the ball driving mechanism, substantially as specified.

2. The combination with a frame adapted to be placed in communication with an electric bell, and a track pivoted at one side of its center thereto incapable of other thanan inclined position, and adapted to make and break the electric circuit, of a weight mov able upon the track and adapted when actuated to traverse the track in both the directions,and mechanism foractuating the weigh t, substantially as specified.

3. The combination with a frame adapted to be placed in communication with an electric bell, and a track pivoted at one side of its center thereto incapable of other than an inclined position, and adapted to make and break the electric circuit, of a weight movable upon the track and adapted when actuated to traverse the track in both the directions, and mechanism independent of the track for actuating the Weight, and means PARKER C. THOMPSON.

\Vi tn esses:

J. OASTERLINE, H. D. MAsTERsoN. 

